javax.servlet.ServletException: Listener refused the connection with the following error:
ORA-12516, TNS:listener could not find available handler with matching protocol stack
The Connection descriptor used by the client was:
(DESCRIPTION=(ADDRESS_LIST=(LOAD_BALANCE=on)(ADDRESS=(PROTOCOL=tcp)(HOST=127.0.0.1)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME=XE)))

javax.servlet.ServletException: Listener refused the connection with the following error:
ORA-12516, TNS:listener could not find available handler with matching protocol stack
The Connection descriptor used by the client was:
(DESCRIPTION=(ADDRESS_LIST=(LOAD_BALANCE=on)(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME=XE)))